• 센서학회지
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• 제5권4호
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• pp.41-46
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• 1996

변압기 절연유중 용존수소를 감지하기 위해 Pd/Pt 게이트 MISFET 센서를 제조하고 그 특성을 조사하였다. 동일 칩안에 내장형 히터와 온도측정용 다이오드를 제조하고 MISFET의 전압 드리프트를 줄이기 위해 차동형구조로 하였다. 수소유입 드리프트를 줄이기 위해, 양쪽 FET의 게이트 절연층을 실리콘 산화막과 실리콘 질화막의 2중 구조로 하였다. 수소감지막의 블리스터를 줄이기 위해 Pd/Pt 2중 금속층을 증착하였다. 제조된 센서의 변압기 절연유에 대한 수소감지 특성은 40mV/10ppm 감도와 0.14mV/day 안정도를 보였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 추계학술대회 논문집 학회본부 C
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• pp.616-618
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• 2000

This paper describes the recent research and technical trend of power cable system. Compact sizing with long length and large capacity is the main trend of the power cable. From the manufacturing process to the monitoring of the underground power line, various new techniques are being developed for reliability and high quality such as in-line monitoring system, triple common extrusion, PD measurement system, new type completion test, etc.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 C
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• pp.1975-1978
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• 2004

We developed internal and external type sensor to measure ultra-high frequency (UHF) partial discharge (PD) in 170 kV gas-insulated switchgears (GIS). We also manufactured a PD-generator to verify and measure the detection sensitivity of those sensors. We measured the output power of the UHF PD sensors induced by PDs of 5 pC using the PD-generator. We measured UHF propagation loss of an 170 kV GIS for optimal arrangement of the sensors. We used swept UHF signal from a network analyzer into the GIS to measure the loss of various components of the GIS.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 춘계학술대회 논문집 전기설비전문위원
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• pp.113-116
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• 2004

We developed internal and external type sensor to measure ultra-high frequency (UHF) partial discharge (PD) in 170 kV gas-insulated switchgears (GIS). We also manufactured a PD-generator to verify and measure the detection sensitivity of those sensors. We measured the output power of the UHF PD sensors induced by PDs of 5 pC using the PD-generator. We measured UHF propagation loss of an 170 kV GIS for optimal arrangement of the sensors. We used swept UHF signal from a network analyzer into the GIS to measure the loss of various components of the GIS.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.2040-2041
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• 2007

In this paper, the UHF PD(Partial Discharge) sensors for $SF_6$ insulated MV $SF_6$ switchgear have been proposed and related investigations have been performed in order to detect the PD which were produced inside the MV $SF_6$ switchgear. Firstly, the internal type UHF PD sensor based on spiral antenna theory has been developed. This type sensor is highly sensitive and has lowly effect on by on-site noise. Secondly, the external type UHF PD sensor was developed based on log periodic antenna concept. This type sensor is removable and detectable for operating switchgear. These sensors were designed and simulated using RF simulation tool. In order to verify the sensitivity of these sensors, we performed the on-site test using the mock-up switchgears including the artificial defects which were the protrusion on high voltage conductor, free moving metal particle and surface defect on insulator. These mock-up switchgear were installed on the test distribution line.

• 정보학연구
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• 제7권4호
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• pp.61-69
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• 2004

본 논문에서는 6.6kV급 고압전동기 모델 코일을 4가지의 권선의 인공적인 결함을 갖도록 제작하였다. 운전중 모의를 위해 모델 코일에 80pF의 에폭시-마이카 커플러를 설치하였으며, TGA를 사용하여 NQN, 부분방전 크기 및 부분방전 패턴 등을 측정하였다. 웨이블렛 변환기법을 이용한 고압전동기의 고정자권선의 결함에서 발생된 부분방전신호의 파형을 통하여 여러 가지의 통계적인 파라메터를 통하여 특징을 추출하였다.

• Mass Spectrometry Letters
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• 제13권4호
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• pp.146-151
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• 2022

Rotigotine (RTG) is a non-ergot dopamine agonist used to manage the early stage of Parkinson's disease (PD) as transdermal patch. However, the poor medication compliance of PD patients and skin issues related with repeated applications of RTG patches lead to the search for alternative formulations and it also requires appropriate analytical methods for their in vivo evaluation. Thus, here, a sensitive, efficient, and cost-effective method to determine RTG in rat plasma using liquid-liquid extraction (LLE) and multiple reaction monitoring was developed. The use of 20 µL of rat plasma for sample treatment, 8-OH-DPAT as the internal standard, and methyl tert-butyl ether as the LLE solvent in the present method gives it advantages over previous methods for the analysis of RTG in biological samples. The good analytical performance of the developed method was confirmed in specificity, linearity (the coefficient of determination ≥0.999 within 0.1-100 ng/mL), sensitivity (the lower limit of quantitation at 0.1 ng/mL), accuracy (81.00-115.05%), precision (≤10.75%), and recovery (81.00-104.48%) by following the FDA guidelines. Finally, the applicability test of the validated method to the in vivo evaluation of a RTG formulation showed that the present method is the only method which can be accurately applied to that longer than 24 hours, critical for the development of formulations with reduced dosing frequencies. Therefore, the present method could contribute to the development of new RTG formulations helpful to people suffering from PD.

• 한국대기환경학회지
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• 제17권5호
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• pp.395-405
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• 2001

To make an assessment of the compatibility between DOAS and conventional point monitoring system (MCSAM-2: MS2), we investigated the concentrations of three criteria pollutants which include S $O_2$, N $O_2$, and $O_3$from a national monitoring station in Seoul during the periods of June 1999~August 2000. The average concentration values for the whole study period derived from hourly concentration data sets of those three species indicated that the mean differences between the two methods can be approximated as 18%. When the bias structure of two systems was evaluated through the computation of percent difference(PD) between the two such as ( $C_{DOAS}$- $C_{conventional}$ $C_{DOAS}$*100, differences between the two systems appeared to be quite systematic among different compounds. While the mode of bias peaked at 0~20% or 20~40% in terms of PD values, the cause of such positive bias mainly arised from generally enhanced concentration values of DOAS system. The structure of bias among different species was further assessed through linear regression analysis. Results of the analysis indicated that the dominant portions of differences observed from two monitoring systems can be accounted for by the systematic differences in their spanning and zeroing systems. S $O_2$(MS2)=0.6385 S $O_2$(DOAS)+2.0985($r^2$=0.7894) N $O_2$(MS2)=0.6548 N $O_2$(DOAS)+7.437($r^2$=0.7687) $O_3$(MS2)=1.0359 $O_3$(DOAS)-7.7885($r^2$=0.7944) The findings of slope values at around 0.64~0.65 from two species suggest that DOAS should respond more sensitively in upper bound concentration range. The offset values apart from zero indicate that more deliberate comparison needs to be made between these monitoring systems. However, based on the existence of strong correlations from at least 8,000 data points for each species of comparison, we were able to conclude that the compatibility of two monitoring systems is highly significant. With the improvement of calibration techniques for the DOAS system. its applicability for routine monitoring of airborne pollutant species is expected to be quite extendable.

• Journal of Korean Neurosurgical Society
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• 제44권1호
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• pp.26-35
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• 2008

Objective : In the evaluation of patients with Parkinson's disease (PD), most neurologists only see their patients during a limited period of their fluctuating 24-hour-a-day lives. This study aimed to assess the short-term outcome of STN stimulation for patients with advanced PD evaluated in a 24-hour monitoring unit for movement disorder (MUMD) using a prospective protocol. Methods : Forty-two patients with advanced PD consecutively treated with bilateral STN stimulation using multi-channel microelectrode recording were included in this study. All patients were evaluated using a 24-hour MUMD with a video recording/editing system and were evaluated with a prospective protocol of the Unified Parkinson's Disease Rating Scale, Hoehn and Yahr Staging, Schwab and England Activities of Daily Living, levodopa equivalent daily dose (LEDD), Short Form-36 Health Survey, and neuropsychological tests. Magnetic resonance (MR) images of the brain were performed prior to and six months after surgery. Results : All patients were evaluated at three and six months after surgery. There was a rapid and significant improvement of the motor symptoms, especially in tremor and rigidity, after STN stimulation with low morbidity. Dyskinesia was markedly decreased with much lowered LEDD values by 50% after STN stimulation. 1.5T MR images were safely taken according to the manufacturer's guidelines at six months after surgery without any adverse effects in 41 patients treated with STN stimulations. Conclusion : Evaluations in a 24-hour monitoring unit could reduce the dose of medication efficiently to an optimal level with patients' comfort and improve the clinical symptoms in harmony with STN stimulation.

• International Journal of Ocean System Engineering
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• 제3권1호
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• pp.16-21
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• 2013

This paper presents a design of fuzzy PD depth controller for the autonomous underwater vehicle entitled KAUV-1. The vehicle is shaped like a torpedo with light weight and small size and used for marine exploration and monitoring. The KAUV-1 has a unique ducted propeller located at aft end with yawing actuation acting as a rudder. For depth control, the KAUV-1 uses a mass shifter mechanism to change its center of gravity, consequently, can control pitch angle and depth of the vehicle. A design of classical PD depth controller for the KAUV-1 was presented and analyzed. However, it has inherent drawback of gains, which is their values are fixed. Meanwhile, in different operation modes, vehicle dynamics might have different effects on the behavior of the vehicle. In this reason, control gains need to be appropriately changed according to vehicle operating states for better performance. This paper presents a self-tuning gain for depth controller using the fuzzy logic method which is based on the classical PD controller. The self-tuning gains are outputs of fuzzy logic blocks. The performance of the self-tuning gain controller is simulated using Matlab/Simulink and is compared with that of the classical PD controller.